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// SPDX-License-Identifier: GPL-2.0-or-later
/*
* (C) Copyright 2011, Franck JULLIEN, <elec4fun@gmail.com>
*/
#include <common.h>
#include <driver.h>
#include <init.h>
#include <malloc.h>
#include <io.h>
#include <asm/nios2-io.h>
struct altera_serial_priv {
struct console_device cdev;
void __iomem *regs;
};
static int altera_serial_setbaudrate(struct console_device *cdev, int baudrate)
{
struct altera_serial_priv *priv = container_of(cdev,
struct altera_serial_priv, cdev);
struct nios_uart *uart = priv->regs;
uint16_t div;
div = (CPU_FREQ / baudrate) - 1;
writew(div, &uart->divisor);
return 0;
}
static void altera_serial_putc(struct console_device *cdev, char c)
{
struct altera_serial_priv *priv = container_of(cdev,
struct altera_serial_priv, cdev);
struct nios_uart *uart = priv->regs;
while ((readw(&uart->status) & NIOS_UART_TRDY) == 0);
writew(c, &uart->txdata);
}
static int altera_serial_tstc(struct console_device *cdev)
{
struct altera_serial_priv *priv = container_of(cdev,
struct altera_serial_priv, cdev);
struct nios_uart *uart = priv->regs;
return readw(&uart->status) & NIOS_UART_RRDY;
}
static int altera_serial_getc(struct console_device *cdev)
{
struct altera_serial_priv *priv = container_of(cdev,
struct altera_serial_priv, cdev);
struct nios_uart *uart = priv->regs;
while (altera_serial_tstc(cdev) == 0);
return readw(&uart->rxdata) & 0x000000FF;
}
static int altera_serial_probe(struct device *dev)
{
struct resource *iores;
struct console_device *cdev;
struct altera_serial_priv *priv;
priv = xzalloc(sizeof(*priv));
cdev = &priv->cdev;
iores = dev_request_mem_resource(dev, 0);
if (IS_ERR(iores))
return PTR_ERR(iores);
priv->regs = IOMEM(iores->start);
cdev->dev = dev;
cdev->tstc = altera_serial_tstc;
cdev->putc = altera_serial_putc;
cdev->getc = altera_serial_getc;
cdev->setbrg = altera_serial_setbaudrate;
console_register(cdev);
return 0;
}
static struct driver_d altera_serial_driver = {
.name = "altera_serial",
.probe = altera_serial_probe,
};
console_platform_driver(altera_serial_driver);
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